Terminate vbscript after x minutes - time

Question

I am working on a script with vbscript, and I would like it to terminate itself after x number of minutes.
I was thinking something like grabbing the time when the script starts and then keeping the whole thing in a loop until the time is x number of minutes after the start time, but I need it to keep checking in the background, and not just wait until a loop is complete.
I want a message or something that notifies the user they took too long, which I can do myself.
Is there any way to keep track of the time in the background, or will it be a bit of a drawn-out process to determine it?

Answer 1

Re-launching the script with //T:xx as suggested by Ekkehard.Horner is probably your best option. Another, slightly different, approach could look like this:
Const Timeout = 4 'minutes
timedOut = False
If WScript.Arguments.Named.Exists("relaunch") Then
'your code here
Else
limit = DateAdd("n", Timeout, Now)
cmd = "wscript.exe """ & WScript.ScriptFullName & """ /relaunch"
Set p = CreateObject("WScript.Shell").Exec(cmd)
Do While p.Status = 0
If Now < limit Then
WScript.Sleep 100
Else
On Error Resume Next 'to ignore "invalid window handle" errors
p.Terminate
On Error Goto 0
timedOut = True
End If
Loop
End If
If timedOut Then WScript.Echo "Script timed out."
You'd still be re-launching the script, but in this case it's your script killing the child process, not the script interpreter.

Answer 2

Here is another short and elegant solution which allows to terminate both the script and the external executable ran asynchronously, via WScript.Timeout
Option Explicit
Dim oSmallWrapperWshExec
WScript.Timeout = 7
Set oSmallWrapperWshExec = New cSmallWrapperWshExec
' Some code here
MsgBox "Waiting timeout" & vbCrLf & vbCrLf & "You may close notepad manually and/or press OK to finish script immediately"
Class cSmallWrapperWshExec
Private oWshShell
Private oWshExec
Private Sub Class_Initialize()
Set oWshShell = CreateObject("WSCript.Shell")
With oWshShell
Set oWshExec = .Exec("notepad")
.PopUp "Launched executable", 2, , 64
End With
End Sub
Private Sub Class_Terminate()
On Error Resume Next
With oWshShell
If oWshExec.Status <> 0 Then
.PopUp "Executable has been already terminated", 2, , 64
Else
oWshExec.Terminate
.PopUp "Terminated executable", 2, , 64
End If
End With
End Sub
End Class

Answer 3

I appreciate all of the answers here, but they are more complicated than I wanted to get in to.
I was very surprised to find out that there is a way to do it built into WScript.
WScript.Timeout = x_seconds

Answer 4

cscript
Usage: CScript scriptname.extension [option...] [arguments...]
Options:
//B Batch mode: Suppresses script errors and prompts from displaying
//D Enable Active Debugging
//E:engine Use engine for executing script
//H:CScript Changes the default script host to CScript.exe
//H:WScript Changes the default script host to WScript.exe (default)
//I Interactive mode (default, opposite of //B)
//Job:xxxx Execute a WSF job
//Logo Display logo (default)
//Nologo Prevent logo display: No banner will be shown at execution time
//S Save current command line options for this user
**//T:nn Time out in seconds: Maximum time a script is permitted to run**
//X Execute script in debugger
//U Use Unicode for redirected I/O from the console
Update:
To help people who downvote a plain (and to the point) citation of cscript.exe's usage message (how can that be wrong?) to see the light through #PanayotKarabakalov's smoke screen:
The claim:
using //T switch not guarantee real time accuracy
that all 5 Echo command executed, even if the Sleep time between them
is 1.5 second and the //T is set to 4
The evidence:
The script is restarted via:
CreateObject("WScript.Shell").Run "WScript " & _
Chr(34) & WScript.ScriptFullName & _
Chr(34) & " /T:4", 0, False
which does not contain the host-specific //T (as opposed to the script-specific /T) switch.
The (counter) argument:
Whatever way you start the first instance of the script (//T or no //T), the second/relaunched instance will never have a time out and will always run to the bitter end.
If you still have doubts, change the invocation in P.'s script to
CreateObject("WScript.Shell").Run "WScript //T:4 " & _
and try it out.